Food authentication

Determination of food authenticity is a topic of increasing importance in food quality control laboratories, for a number of reasons. On the one hand, the appearance of diseases linked to a particular foodstuff, originating from a particular region, makes it necessary to ensure that it is possible to control this aspect in order to ensure consumer safety. On the other hand, there are certain agricultural products and foodstuffs that are produced, processed, and/or prepared in a particular geographical region with a recognized know-how. This has led to the 

chemical analysis plays a crucial role in this type of forensic work. A wide variety of techniques can be used to achieve information on a product that can be linked to its origin [36, 37], but the use of ICP-MS to obtain trace element and isotopic information is becoming more popular. 

The sample that has attracted most attention so far, and that was studied first, is wine [62]. This is logical, because it is a product of great social, economic, and cultural relevance, and its quality and price are linked to the area of grape collection and wine production. The evolution of the instrumentation selected for analysis can be also perceived in Table 14.3, with a tendency to use MC-ICP-MS preferentially in the last 5 years. Moreover, during this period, other food products have also received attention. 

Already in 1997, Augagneur et al. compared the performance of quadrupole-based ICP-MS with that of TIMS for Pb isotopic analysis of wine samples. They concluded that there was good agreement between the results provided by the two techniques, and reported a precision for quadrupole-based ICP-MS ranging between 0.1 and 0.3% RSD for ratios involving ° Pb, ° Pb, and ° Pb [38]. 

Wine samples from different Pb isotope ratios Q-ICP-MS [41] 

8 Further Examples, Food Authentication 9.8.1 Food Authentication 

Natural products such as wine, fruit juices, flavors, oils, and honey are prime targets for fraudulent adulteration because of their high prices. Sophisticated analytical methods (perhaps including isotope abundance measurements) are required to detect whether natural ingredients have been mixed with ones from cheaper synthetic sources. Isotope abundance is markedly different for natural vs. synthetic molecules and these differences can be exploited to detect adulteration. Several examples follow. 

The major adulteration problem in fruit products is addition of sugar. The simplest method of extending a fruit juice is to add inexpensive sugar and dilute with water to rebalance sweetness. Since most juices are extracted from C4 plants (813C 15%o), and adulterating sugars from corn syrup or cane sugar are from C3 

Honey and maple syrup are complex products of high market price (813C — 23%o). The main source of adulteration is cheap high fructose corn syrup (813C — 13%o) or cane sugar (813C —ll%o) and the adulterated product is easily detected at levels as low as 10% or so of added sugar. 

9 Isotope Effects in Nature Geochemical and Environmental Studies 

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Wrolstad, R.E. and Durst, R.W., Use of anthocyanin and polyphenohe analyses in authenticating fruit juices, in Proceedings of Food Authenticity Workshop, ENl Laboratories, Ed., Eurofins Scientific International Group, Montreal, 1998. 

Lees, M. (2003). Food Authenticity and Traceability. Woodhead Publishing Ltd., Cambridge, UK. 

Martin, P., Sharman, M., and Scotter, C. N. G. (1998). Honey-product definition and manufacturing processes. In "Food Authenticity-Issues and Methodologies", (M. Lees, Ed.), pp. 169-182. Eurofin Scientific, Nantes, France. 

Molan, P. (1996). Authenticity of honey. In "Food Authentication", (P. R. Ashhurst and M. Dennis, Eds), pp. 259-303. Blackie Academic and Professional, London. 

Abstract The application of isotope effect studies to problems in geochemistry and geology, meteorology, environmental studies, archeology and paleobotany, food authentication, medical diagnostics and various other practical areas is described using numerous examples. 

Zawirska-Wojtasiak R, Chirality and the nature of food authenticity of aroma, Acta Set Pol TechnolAliment, 5 21-36, 2006. 

Recently, Peace and Gilani [229] reviewed chromatographic determination of amino acids. HPLC analysis of free amino acids can be a powerful tool in the control of food authenticity. Cotte et al. [230] demonstrated that HPLC analysis of free amino acids, followed by statistical processing of... 

IRMS has become more and more important in food authenticity assessment, since cGC, coupled online via a suitable combustion/pyrolysis interface with IRMS has been realised. The substances eluted from the cGC column are converted into the corresponding gas (carbon dioxide, nitrogen, hydrogen and car-... 

Food authentication Wheat varietal identification Reversed-phase 125-128... 

MJ Dennis, PR Ashurst. An introduction to food authentication. In PR Ashurst, MJ Dennis, eds. Food Authentication. London Chapman Hall, 1996, pp 1-14. 

The analytical detection and measurement of fruit juice adulterants is a rapidly developing field and the interested reader is directed to works dealing specifically with the subject, such as Food Authentication (Ashurst Dennis,... 

Ashurst, P.R. and Dennis, MJ. (eds) (1996) Food Authentication, Blackie Academic Professional, Chapman Hall, London. 

A particular mention is needed for describing one analytical technique capable of detecting the exact site-specific isotope ratio. This technique, called SNIF-NMR (site specific natural isotope fractionating technique), constitutes the most specific and sophisticated method used for food authenticity determination. 

Food authentication is the process by which a food is verified as complying with its label description. Authenticity problems are directly associated with the labelling of a product and compositional regulations, which may differ from country to country and that have a fundamental place in determining which scientific tests are appropriate for a particular issue. 

In the last years, the aim of our research was to investigate the potential of the gas and liquid sensor arrays for food authentication and quality control investigation on the freshness evolution of Italian Crescenza cheeses, characterisation and classification of honey of different botanical and geographical origin, and characterisation and classification of Italian Barbera wines. 

Baeten, V., Michotte Renier, A., Sinnaeve, G. and Dardenne, P. (2001) Analyses of feed-ingstuffs by near-infrared microscopy (NIRM) detection and quantification of meat and bone meal (MBM), Proceedings of the Sixth International Symposium on Food Authenticity and Safety, 28-30 November 2000, Nantes, pp. 1-11. 

Food authentication is one of the major areas involved in food quality and safety. Several regulations have been implemented to assure correct information and to avoid species substitutions (26). Food species identification has traditionally relied on morphological/anatomical analysis. However, this is a difficult task in the case of closely related species and especially for those products that have been subjected to processing practices. Therefore, there is a strong need for fast and reliable molecular identification methods that provide authorities and food industries the tools needed to comply with labeling and traceability requirements, thus ensuring product quality and protection of the consumer. 

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